One of the foundational qualities of the Bible is its clarity (sometimes called perspicuity). That means Scripture's main teachings are plain enough to be understood without the need of special expertise or church-sanctioned interpretations.
The Bible frequently speaks about its own clarity. Psalm 119:130 says, "The unfolding of Thy words gives light; it gives understanding to the simple." The average person who humbly reads the Bible can say, "I have more insight than all my teachers, for Thy testimonies are my meditation" (Psalm 119:99). Psalm 19:7 teaches, "The testimony of the Lord is sure, making wise the simple."
The idea of hidden codes in the Bible contradicts all of that by limiting accessibility to the real message of the Bible to so-called experts who can decipher the cryptic messages God "hid" in the Scriptures. But such "experts" aren't needed because the Bible contains no hidden codes.
One hidden-code theory works like a common word-search puzzle--hidden messages are supposedly embedded diagonally within the Hebrew text. But that's as foolish as turning your daily newspaper into a word-search puzzle and expecting to find meaningful stories hidden in it. Newspapers aren't written to convey messages in secret code, and neither was the Bible. Both should be read using ordinary rules of language.
Of course there are concepts in the Bible that are hard to understand--even the apostle Peter admitted that (2 Peter 3:15). But the way to discover the meaning of those hard passages is not by seeking out hidden messages, but by engaging in diligent study that accurately handles the word of truth (2 Timothy 2:15).
Take heart! The Bible is clear and even the most untrained reader can understand it. God wants you to understand the Bible, and He has provided the Holy Spirit as a guide. After all, "man does not live by bread alone, but...by everything that proceeds out of the mouth of the LORD" (Deuteronomy 8:3).